1. Field of the Invention
The present invention relates to an arrangement designed to improve the ability of payphones to collect accounting data and to monitor payphone events by providing sensors to monitor events such as the removal of the front cover, vault door and coin box. In a preferred embodiment, specially designed brackets containing low power sensors are used to retrofit pre-existing standard hardware to have data or event monitoring capacity. These brackets and sensor arrangements use pre-existing openings and mounting screws located within standard payphone housings thereby allowing easy retrofitting.
2. Description of the Prior Art
It has long been recognized that it is desirable to monitor payphone events and to collect data for audit purposes and the like. For example, it is desirable to be able to monitor both the time and fact of the opening or removal of the vault door which provides a serviceman access to the coin box, as well as removal of the coin box itself.
Additionally, it is desirable to monitor the removal of the front cover which is located above the vault door. Circuits controlling payphone operation are located behind this cover, and a repairman gains access to those circuits by removing this cover.
U.S. Pat. No. 4,567,325 discloses a controller for a coin operated telephone set which incorporates automatic trouble reporting circuitry. A stuck coin indication is provided to a central office, while a microcomputer checks the telephone circuitry and coin chute to determine if they are operational. If they are deemed non-operational, then the stuck coin signal remains until a repair visit corrects the situation. The circuitry described does not monitor the front cover, vault door or coin box. Additionally, the circuits are not described as being low-power and further would apparently not operate if payphone power is cut.
U.S. Pat. No. 4,625,078 discloses a method for fraud prevention in an electronic telephone set. A local memory for storing coin deposit information and generating coin deposit signals is disclosed. This memory is said to be capable of being interrogated remotely by a central office. A cash box detector comprising a mechanical switch which changes state each time a cash box vault door is removed, is described. Additionally, three infrared LED-phototransistor pairs monitor coins entering and leaving the coin chute, and a hopper-overflow LED senses cash box overflow. These optical sensor arrangements may be unreliable, however, because of problems associated with optical sensors such as fouling due to dirt, and require a constant supply of power in order to operate to detect the occurrence of an event.